For example, the following patent document 1 describes a cap unit (b) for puncture repair. The cap unit (b) is secured to a mouth portion (a1) of a bottle container (a) as shown in FIG. 6. With compressed air from a compressor (d), a puncture repair liquid and the compressed air are sequentially charged into a punctured ti re (t) to temporarily repair the puncture.
The cap unit (b) includes a cap body (g) including first and second flow channels (e) and (f), and a lid-shaped closing plug (h) to simultaneously close the first and second flow channels (e) and (f). The first flow channel (e) is the flow channel to feed the compressed air from the compressor (d) into the bottle container (a). The second flow channel (f) is the flow channel to sequentially take out the puncture repair liquid and the compressed air from the bottle container (a) by a feed of the compressed air.
Specifically, the cap body (g) includes a securing recess portion (g1) to screw thereto the mouth portion (a1) of the bottle container (a), and a boss portion (g2) extending upward from a bottom surface of the securing recess portion (g1). An outer peripheral surface of the boss portion (g2) defines a closing plug securing portion (j) to allow the closing plug (h) to be elastically fitted thereto. The boss portion (g2) includes upper opening portions (e1) and (fi) respectively for the first and second flow channels (e) and (f), which are disposed further inside than the closing plug securing portion (j). The closing plug (h) integrally includes a closing plug body (ha) and a plug shank portion (hb). The closing plug body (ha) is to be fitted to the outer peripheral surface of the boss portion (g2) (the closing plug securing portion (j)) so as to close the first flow channel (e). The plug shank portion (hb) is to be fitted into the upper opening portion (f1) so as to close the second flow channel (f).
The cap unit (b) is subjected to on-vehicle storage in a mount state in which the cap unit (b) mounts thereon the bottle container (a). At the time of a puncture repair, the cap unit (b) in the mount state is to be piped to operate the compressor (d). This allows the compressed air to flow through the first flow channel (e) into the closing plug body (ha). Then, upon an increase in internal pressure of the closing plug body (ha), the closing plug (h) is to automatically disengage. That is, the first and second flow channels (e) and (f) are to be opened.
Accordingly, the closing plug (h) does not need to disengage during the storage, and needs to easily disengage with the compressed air at the time of the puncture repair. Therefore, enhanced precision in fitting dimension between the closing plug (h) and the cap body (g), and high precision control of an interlocking force between the closing plug (h) and the cap body (g) are respectively required.
However, with the conventional structure, interlocking variations occur in both the closing plug body (ha) and the plug shank portion (hb). Hence, further enhanced precision is needed for the fitting dimension, thus leading to a drop in yield rate and an increase in process costs for a product inspection process.
Additionally, the conventional structure needs simultaneous disengagement in the fitting of the closing plug body (ha) and the fitting of the plug shank portion (hb). When the plug shank portion (hb) is first about to disengage to cause a gap, the compressed air in the closing plug body (ha) leaks from the gap to the second flow channel (f). Consequently, the internal pressure of the closing plug body (ha) stops increasing, and the closing plug (h) does not disengage from the boss portion (g2). On the other hand, when the closing plug body (ha) is first about to disengage to cause a gap, the compressed air leaks from the gap into the bottle container (a). Consequently, the pressure in the bottle container (a) increases to decrease a pressure difference between the inside and outside of the closing plug body (ha). Consequently, also in this case, the closing plug (h) does not disengage from the boss portion (g2). Thus, the closing plug body (ha) and the plug shank portion (hb) need to disengage simultaneously, and this also contributes to the need for high precision.